#!/bin/bash
#
# Copyright 2016 Istio Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
################################################################################
#

ROOT="$(git rev-parse --show-toplevel)"
SKIP="$(git config --bool hooks.clang-format.skip)"

if [[ "${SKIP}" == "true" ]]; then
  echo "Skipping clang-format since it's disabled."
  exit 0
fi

CLANG_DIRECTORY="${HOME}/clang"
CLANG_FORMAT="${CLANG_DIRECTORY}/bin/clang-format"
if [[ ! -x "${CLANG_FORMAT}" ]]; then
  CLANG_FORMAT="$(command -v clang-format)"
fi

if [[ ! -x "${CLANG_FORMAT}" ]]; then
  echo "Skipping clang-format: " \
      "\"${CLANG_FORMAT}\" doesn't exists or not executable"
  exit 0
fi

CLANG_FORMAT_VERSION="$(${CLANG_FORMAT} -version | cut -d ' ' -f 3)"
CLANG_FORMAT_VERSION_REQUIRED="3.8.0"
if ! [[ "${CLANG_FORMAT_VERSION}" =~ "${CLANG_FORMAT_VERSION_REQUIRED}" ]]; then
  echo "Skipping: clang-format ${CLANG_FORMAT_VERSION_REQUIRED} required."
  exit 0
fi

DIRTY_FILES=($(git diff --name-only | grep -E '\.(h|c|cc|proto)$'))
if [[ "${#DIRTY_FILES}" -ne 0 ]]; then
  echo "Found dirty files: ${DIRTY_FILES[@]}"
  echo "stash or add them before commit."
  exit 1
fi

SOURCE_FILES=($(git ls-files | grep -E '\.(h|c|cc|proto)$'))

if [[ "${#SOURCE_FILES}" -ne 0 ]]; then
  pushd "${ROOT}" > /dev/null
  "${CLANG_FORMAT}" -style=Google -i "${SOURCE_FILES[@]}"
  git add "${SOURCE_FILES[@]}"
  echo "Formatted all source codes"
  popd > /dev/null
else
  echo "No source files."
fi

BUILDIFIER="$(which buildifier)"
if [[ -x "${BUILDIFIER}" ]]; then
  ${BUILDIFIER} -showlog -mode=check $(find . -iname BUILD -type f)
else
  echo "Buildifier does not exist"
fi
